1. Field of the Invention
The present invention relates to a device for feeding can barrels such as bottomed can barrels for can containers with their axes lying horizontally while rotating them through a prescribed angle.
2. Description of the Prior Art
One known device for feeding can barrels is disclosed in U.S. Pat. No 4,246,300, for example.
As shown in FIGS. 7 and 8 of the accompanying drawings, can barrels a for can containers are supplied with their axes lying horizontally from a vertical supply path b into receiver slots d defined by a star wheel c as it rotates. The supplied can barrels a have their bottoms g attracted by respective attracting rollers f which are rotated by an endless belt e disposed behind the star wheel c and having suction holes fl coupled to a suction device (not shown). Upon rotation of the start wheel c, the can barrels a held horizontally by the attracting rollers f are successively angularly moved through a prescribed angle while being rotated about their own axes by the rotation of the attracting rollers f about their own axes. At each position S of the angular movement, paint is sprayed into the can barrel a to apply a paint coating to its inner surfaces. Then, the painted can barrel a is further rotated through a certain angle, and then released from the attracting roller f onto a feed conveyor h by which the can barrel a is delivered into a drying oven device (not shown) in which the applied paint coating is dried with heat.
When the bottom of the can barrel a is attracted to the attracting roller f, it is necessary to align the center of rotation of the attracting roller f with the center of the bottom of the can barrel a. If the centers are not properly aligned with each other, the can barrel a attracted to the attracting roller f would be rotated in an eccentric condition. For centering the can barrels a, the conventional device has a side guide j having a guide surface m extending in concentric relation to the star wheel c which holds the can barrels a. The can barrel a can not be accurately centered with respect to the attracting roller f if the can barrel a is attracted to the attracting roller f during the process of aligning the center of the bottom of the can barrel a with the center of rotation of the attracting roller f. Therefore, the can barrel a is attracted to the attracting roller f only after the can barrel a is centered at the time it is held and rotated by the star wheel c at the terminal end of the supply path b. It is also proposed to provide the attracting roller f with a centering boss for fitting in a recess in the bottom of the can barrel a and to provide a top guide 1 for engaging the open end k of the can barrel a.
With the disclosed conventional arrangement, the attracting roller f is rotating about its own axis when the can barrel a is supplied from the supply path b into the receiver slot d of the rotating star wheel c, centered with respect to the attracting roller f and attracted thereto. Therefore, before the bottom g of the can barrel a which is not rotated is attracted to the attracting roller f at a prescribed position thereon, the can barrel a may wobble out of centered alignment into a twisted shape. The can barrel a is centered while being gripped between the star wheel c and the side guide j. Consequently, when the can barrel a is rotated by the rotation of the attracting roller f about its own axis, the can barrel a tends to be damaged since its side i is held against the receiver slot d and the side guide j The can barrel a is also gripped between the attracting roller f and the top guide 1 with the open end k of the can barrel a being in contact with the top guide 1. Therefore, upon rotation of the can barrel a caused by the attracting roller f about its own axis, the open end k tends to be deformed by pressed engagement with the top guide 1. If the side i of the can barrel a is damaged, the can barrel a has a poor appearance. If the open end k is deformed, it cannot smoothly be flanged at a later time.